FDA approves Arena's weight-loss drug

Arena Pharmaceuticals' Belviq (lorcaserin) has broken the ice in the prescription drug category for weight loss. Today the FDA approved it as an adjunct to diet and increased physical exercise for chronic weight management in overweight and obese adults.

The first anti-obesity drug to be approved in the US in over a decade, Belviq will be launched in the states by Eisai, once the drug receives DEA scheduling. The drug's label does not include a REMS that could have limited the patient pool.

The FDA is requiring Arena to conduct, along with six post-marketing studies, a long-term study to assess cardiovascular outcomes. The latter has been a segment-wide issue for decades, making the product name Fen-Phen (fenfluramine) short-hand for the heart risks that have dogged the weight-loss drug category before and since. In this case, the need for a new treatment option seemed to outweigh those risks.

The agency's OK follows an advisory panel's 18-4-1 endorsement in May, a vote which belied panelists' concerns about how the drug could damage heart valves. Its effect on cardiovascular morbidity and mortality have not been established. Belviq, formerly known as Lorqess, was dismissed in 2010 by the FDA over heart valve concerns and reports that it caused cancer in lab rats.

“The approval of this drug, used responsibly in combination with a healthy diet and lifestyle, provides treatment options for Americans who are obese or are overweight and have a least one related comorbid condition,” Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research said in a statement.

In clinical trials, about 42% of patients without type 2 diabetes achieved 5% weight loss at 12 weeks. Among patients with type 2 diabetes, 32% of them achieved 5% weight loss at three months. Belviq's active ingredient is believed to decrease food consumption and increase satiety by targeting receptors in the brain.

The spate of prescription weight loss candidates tracks with more than a desire for thinness – obesity has become such an overwhelming problem that the Centers for Disease Control estimates that more than 35% of American adults are obese. Obesity has been linked to several other conditions, including a rise in diabetes, which is now called and epidemic, heart disease and cancer.

Launch details, pricing or reimbursement information have not been forthcoming. On a conference call with analysts today, Arena CEO Jack Lief termed Belviq a "good fit" with Eisai's primary care and specialty portfolios. "Eisai plans for Belviq to reside within their current field force structure," he said.

Wednesday's "yes" on Belviq also comes several weeks before Vivus is slated to hear an FDA decision about its rival anti-obesity drug, Qnexa, which received a thumbs-up from an FDA panel in February. Another potential competitor, the drug Contrave from Orexigen Therapeutics, was dismissed by the FDA in 2011, also due to concerns related to cardiovascular risk. Earlier this year, Orexigen and the FDA agreed on a protocol for a cardiovascular outcomes trial, and the company is proceeding with development.